Subacute cutaneous lupus erythematosus (SCLE) is a photosensitive form of lupus-specific skin lesion that is strongly associated with the presence of anti-Ro/SSA autoantibody. The pathogenesis of SCLE includes genetic, environmental and immunologic factors. Recent studies provide strong evidence for the involvement of innate and cell-mediated immunity, underlying the important role of plasmacytoid dendritic cells, interferon-alpha and antibody-dependent cell cytotoxicity. In addition, a variety of cytokines, chemokines and adhesion molecules have been found to participate in the expansion phase of the autoimmune effector mechanisms. This article summarizes the recent immunological findings and reviews the current mechanisms which are implied in the development of the disease.